The compounds of formula (I) belong to a known class of compounds related to melatonin agonists. For instance, the substituted 7-allyl-6-hydroxy-indanes of formula (I) wherein R is ethyl and X is bromine, and its (S)-enantiomer, are key intermediates in the process for the preparation of ramelteon, N-[2-[(8S)-1,6,7,8-tetrahydro-2H-indene[5,4-b]furan-8-yl)ethyl]-propionamide, a well known melatonin agonist, and have been prepared from the corresponding substituted 6-allyloxy-indanes (II) by rearrangement of allyl group in N,N-diethylaniline for 2.5 hours at 200-205° C. under argon atmosphere in a 80% yield (U.S. Pat. No. 6,034,239; U.S. Pat. No. 6,218,429; and Uchikawa et al., J. Med. Chem. 2002, 45, 4222-4239). Furthermore, WO 2007109141 discloses fluoro analogs of ramelteon which can be obtained from the corresponding 7-allyl-6-hydroxy-indanes of formula (I) wherein R is ethyl or propyl, and X is fluorine, which in turn are prepared from appropriate intermediates (II) by the same process.